With a sharply uneven edge (6)
I believe the answer is:
jagged
'with a sharply uneven edge' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for jagged that I've seen before include "Serrated" , "Having sharp uneven surface" , "With rough sharp points" , "Having a sharply uneven surface or outline" , "Sharp-edged" .)